By following the Schematics of the NanoPi Fire 3, the Micro usb connector is wired correctly to the processors USB-OTG (excpet the power supply). So, i would expect that an externally powered usb device connected via an otg cable works, but that is not the case . Is there any possibility to get that to work? It would give the nanoPi 3 another 500mbit of i/o power for free